66% Double Hets question

[Ash]

Let me know if I'm wrong about this one.

I've seen ads for "66% double hets", which I assume must have come from a pair of 100% double hets.

Shouldn't they really be 43.5% double hets?

Lets say that you breed a 100% double het lavender pied to another 100% double het. The odds that any normal-looking baby inherits the lavender gene at all is 66%. The odds that any normal-looking baby inherits the pied gene is also 66%. So the odds that they inherit both of them is less likely than just one or the other.

In statistics the odds that any two events occur together/after one another is found by multiplying the odds of each together. (.66)(.66) = .435

Right? I know it's not much of a difference, but still.

[bones93]

By the snake being 66 percent DH that means there is a 66 percent chance of the snake carrying those genes. Does not necessarily mean it has either of the genes mentioned.

[RhacHead]

Punnet squares only represent the possibility of a potential pairing so in theory a 100% het x 100% het means you would have a 1 in 4 chance of hitiing a visual morph then the other 3 out of 4 represent the potential.for the other snakes.2 of the 3 should hold the gene while the other does not hence 66% (2 out of 3) this is true for both genes so it 66% het x2 so yes statistically you would have less of a chance of inheriting both genes but its just much easier to say 66% double het meaning a non visual morph from 2 100% hets. I hope my rambling made sense and was somewhat helpful.

[GenePirate]

Let me know if I'm wrong about this one.

I've seen ads for "66% double hets", which I assume must have come from a pair of 100% double hets.

Shouldn't they really be 43.5% double hets?

Lets say that you breed a 100% double het lavender pied to another 100% double het. The odds that any normal-looking baby inherits the lavender gene at all is 66%. The odds that any normal-looking baby inherits the pied gene is also 66%. So the odds that they inherit both of them is less likely than just one or the other.

In statistics the odds that any two events occur together/after one another is found by multiplying the odds of each together. (.66)(.66) = .435

Right? I know it's not much of a difference, but still.

Yes, you are correct, and yes, 44% is much different than 66%.

[GenePirate]

However, 66% DH can come from (for example) a double het axanthic ghost bred to an axanthic het for ghost.

[Freakie_frog]

However, 66% DH can come from (for example) a double het axanthic ghost bred to an axanthic het for ghost.

They would be 100% het axanthic and 66% het for ghost. Just to clarify

[GenePirate]

They would be 100% het axanthic and 66% het for ghost. Just to clarify

Exactly. That would be the 66% chance that you'd have both genes in the same animal.

[Gloryhound]

On the Punnit square it comes out with odds of 44% of the normals looking offspring of two double gets actually having "both" genes is correct.

The double Het breeding would end in the results of
6.25% Normal
12.5% Normal but being het for Gene A
12.5% Normal but being het for Gene B
25% Het for Gene A and Gene B
6.25% Visible Gene A "Not" het for Gene B
6.25% Visible Gene B "Not" het for Gene A
12.5% Visible Gene A het for Gene B
12.5% Visible Gene B het for Gene A
6.25% Visible Gene A and B (double morph)

Since we are only dealing with the animals that do not have a visible trait we can remove 43.75% of the odds leaving 56.25% of the offspring in the equation. If 56.25% of the off spring now equals 100% of the animals being dealt with the 25% for those truely being double het would equal 44.4% of the offspring being dealt with when done using ratios.

[alan1]

However, 66% DH can come from (for example) a double het axanthic ghost bred to an axanthic het for ghost.

not 'DH' no...

Exactly. That would be the 66% chance that you'd have both genes in the same animal.

correct, but - that would be 'mis-labeling' the animal

They would be 100% het axanthic and 66% het for ghost. Just to clarify

this is correct...

[Freakie_frog]

here is the easiest way to look at it..

when breeding a 100% het x 100% het you get
25% normals
50% het's
25% homo

Since you can't tell the normals for the hets 75% of the clutch is normal looking.
So of the you take 100% of the normal looking animals and since they were statically 75% of the total clutch you divide 100/3 this gives you 33.33%. So say you get 3 normals each normal on its own has a 33.33 % chance at being normal this means that of the 75% of original 100% (or 4 possible outcomes) 2 of them will be 100% het's.
So out of the 3 normal looking outcomes or 100% of the normal looking animals you subtract the 33.33% chance of it being just a normal and your left with 66.66% chance each animal will be a het.